﻿<p>
 <em>IfcMaterialDefinitionRepresentation</em> defines presentation information relating to <em>IfcMaterial</em>. It
 allows for multiple presentations of the same material for different geometric representation contexts.
</p>
<blockquote class="note">
 NOTE&nbsp; The <em>IfcMaterialDefinitionRepresentation</em> is currently only used to define presentation information to
 material used at element occurrences, defined as subtypes of <em>IfcElement</em>, or at element types, defined as subtypes
 of <em>IfcElementType</em>. The <em>IfcMaterial</em> is assigned to the subtype of <em>IfcElement</em>, or <em>IfcElementType</em>
 using the <em>IfcRelAssociatesMaterial</em> relationship (eventually via other material related entities
 <em>IfcMaterialLayerSetUsage</em>, <em>IfcMaterialLayerSet</em>, <em>IfcMaterialLayer</em>, or
 <em>IfcMaterialProfileSetUsage</em>, <em>IfcMaterialProfileSet</em>, <em>IfcMaterialProfile</em>).
</blockquote>
<p>
 The <em>IfcMaterialDefinitionRepresentation</em> can apply
</p>
<ul>
 <li>different presentation styles for different representation contexts, for example, a different style for
  sketch view, model view or plan view, or for different target scales,
 </li>
 <li>for each representation context is can apply curve style, fill area style (hatching), symbol, text and surface style.
 </li>
</ul>
<blockquote class="history">
 HISTORY&nbsp; New entity in IFC2x3.
</blockquote>
<blockquote class="change-ifc2x3">
 IFC2x3 CHANGE&nbsp; The entity <em>IfcMaterialDefinitionRepresentation</em> has been added.
 Upward compatibility for file based exchange is guaranteed.
</blockquote>
<blockquote class="change-ifc2x4">
 IFC4 CHANGE&nbsp; The assignment of curve, surface and other styles to an <em>IfcStyledItem</em> has been simplified
 by <em>IfcStyleAssignmentSelect</em>. The use of intermediate <em>IfcPresentationStyleAssignment</em> is deprecated.
</blockquote>
<p>&nbsp;</p>
<p class="use-head">
 Use definition
</p>

    <table border="0" cellpadding="0" cellspacing="0" summary=
    "use diagram">
      <tr>
        <td valign="top">
          <img src=
          "../../../figures/ifcmaterialdefinitionrepresentation_01.png" alt=
          "use diagram" border="0">
        </td>
	<td>As shown in Figure 2, the presentation assignment can be
      specific to a representation context by adding one and more
      <em>IfcStyledRepresentation</em>'s. Each of them includes a
      single <em>IfcStyledItem</em> with exactly zero or one style
      for either curve, fill area, surface, text or symbol style
      that is applicable.</td>
      </tr>
      <tr>
        <td>
          <p class="figure">Figure 2 &mdash; Material definition representation</p>
        </td>
	<td>&nbsp;</td>
      </tr>
    </table>